Delivering prevention: the role of public programs in delivering care to high-risk populations.

A successful program of prevention or early detection should have a high level of population coverage and should ensure that high-risk populations are targeted. In practice, relatively little attention has been paid to the tendency toward greater use of preventive care by populations at lower risk, in other words, for higher use by the wealthy than by the poor. Current delivery patterns of preventive care raise questions as to how to organize these services more effectively. Physician-based delivery of preventive care in a fee-for-service system seems to result in Canadian patterns of use that are fairly similar to those found in the United States. Universal free insurance alone does not appear to be enough to counteract the failure to target preventive care toward the least-healthy groups. Appropriately-run Canadian provincial programs may be able both to expand coverage and to target high-risk populations. The population coverage for three measures directed toward prevention or early detection--childhood immunization (which in Manitoba has been offered through a long-standing provincial program), screening mammography (a new provincial program), and cervical cancer screening (no provincial program)-are compared using longitudinal administrative data from Manitoba. The discussion emphasizes the role of provincial programs and the possibilities for using population-based data to help provide cost-effective care to high-risk populations.